1. Field of the Invention
The present invention relates generally to level instrument technology and particularly to level vials.
2. Description of the Related Art
Spirit levels are well known instruments used to plumb or set surfaces, such as horizontal or vertical surfaces. The most common spirit levels are the tubular levels and the circular levels.
Tubular spirit and circular bubble levels generally include one or more bubble vials, in which a fluid (e.g., mineral spirits, kerosene, or similar substances) is encapsulated within a sealed transparent (or at least translucent) body with an air space providing a visible bubble. Although glass was originally used to make bubble vials, today, acrylic is the material predominantly used for making molded vials, although other plastics are also used. Circular bubble levels are generally spherically domed shaped buttons, while tubular spirit levels are typically cylindrical shaped inside a rectangular solid.
Circular bubble levels are used for leveling of planes in two dimensions. While generally of greater accuracy than the circular levels, tubular levels can normally determine the level only in one dimension. Thus, when a surface or a device such a tripod has to be leveled with improved precision, a circular level is generally used for a quick but less precise leveling, and then, the precision is improved by using a tubular level in two dimensions. Hence, a user has to use two or more levels and to read two or more vials in order to level the respective tripod.
Furthermore, when tubular spirit vials are used, if the spirit level instrument is to accommodate multiple planar orientations, such as horizontal, vertical and 45 degrees orientations, a separate spirit level vial is usually provided for each planar orientation of interest. Again, the user has to read different vials, one for each planar orientation of interest.
In both examples, the process is cumbersome and time consuming for the user as he/she needs to read multiple vials. Thus, a need exist for better vials and levels, which address these problems.
The problems and the associated solutions presented in this section could be or could have been pursued, but they are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches presented in this section qualify as prior art merely by virtue of their presence in this section of the application.